Some are now accusing Mossad of involvement in the murder of a Hamas leader in Dubai

Jerusalem (CNN) -- The murder in a Dubai hotel room of a Hamas leader has grabbed headlines around the world as rumors and speculation swirl about the team that allegedly assassinated him.

Fingers -- in the media and the intelligence community -- point toward Israel's spy agency Mossad as responsible. The agency is keeping quiet but has a history of operations in the Middle East, South America and Europe.

Dubai's police chief told the Abu Dhabi-based newspaper, The National, he was confident that a Mossad hit squad was behind the assassination of Mahmoud al Mabhouh.

In Israel, editorials have already moved on from asking if Mossad was responsible to querying if Mossad has made a mistake. An editorial in The Haaretz newspaper read: "Assassinations are neither effective nor legal and sometimes not moral -- when the target is a political leader or someone who could have been detained."

But Mossad and the Israeli government has stuck to the policy of ambiguity -- neither confirming nor denying a role in killing Mahmoud al-Mabhouh. By remaining silent, there are less likely to be international repercussions and any intelligence agency in the world likes to keep its enemies guessing.

But many operations in the past have been credited to Mossad. Undoubtedly one of the agency's greatest achievements was capturing Adolf Eichmann, an architect of the Holocaust.

Eichmann was captured in Argentina in 1960 and taken to Israel where he was tried and executed in 1962. It is still the only time Israel ever carried out the death penalty.

Rafi Eitan, head of that Mossad mission, told CNN: "We could have killed him quite easily but we wanted to take him to trial. That was much more difficult."

In 1972, at the Olympic Games in Munich, Germany, Palestinian terrorists killed two Israeli athletes and took nine more hostage, demanding the release of 200 Palestinians. Israel refused and the athletes were killed in a bungled rescue attempt by the German military at the airport.

It became known as the Munich massacre and Golda Meir, then Israeli Prime Minister, said: "It was obviously very well organized by the terrorists and our boys paid for it."

Meir is widely believed to have ordered Mossad to track down the killers. One year later, three Palestinians were killed in Beirut including Mohammad Yusuf al-Najjar, head of Black September, the militant group which carried out the attack.

Over the next few years a handful of other Palestinians believed to have been involved were also assassinated.

But in Lillehammer, Norway, Mossad agents killed the wrong man, a Moroccan who had nothing to do with the attack. Five agents were caught and imprisoned then released to Israel two years later.

Dr. Ronald Bergman, Mossad expert and author of "The secret war with Iran" told CNN: "Throughout the years Mossad earned itself a reputation of an efficient and ruthless intelligence agency with - quote - license to kill."

But an attempt to poison Hamas leader Khaled Meshaal in Jordan in 1997 failed spectacularly.

The Mossad agents were caught and Jordan's late King Hussein forced then-Prime Minister Benjamin Netanyahu - coincidentally he is also Israel's current prime minister -- to send the antidote to save Meshaal and release Hamas' spiritual leader, Sheikh Yassin. Yassin was killed in 2004 when his car was hit by missiles fired from an Israeli military helicopter.

Danny Yatom was head of Mossad at the time and ordered the Mashaal hit.

He told CNN he does not regret the assassination attempt, only the fact it failed. "I think that no terrorist can enjoy any immunity and they should know that the free world will chase them if they continue to execute terror attacks." He agrees with Mossad's policy of not commenting on operations. "Everything should be hidden because it is an unlawful operation in any other territory," he said.

The current head of Mossad, Meir Dagan, is remaining silent, but some Israeli editorials are calling for him to resign if Mossad is found guilty of the hit.